Auto box problems (C MAX)

[Vulgar LS2]

Hi guys, I have a 2007 c max 2.0 auto (petrol).

When you switch on and drive off it will give me 3 out of 4 gears, but once it comes down from 3rd when slowing down it will only go as high as 2nd gear once you are back on the power.

Now, I've got it on a garage lift and with the wheels off the floor it will engage all 4 gears with no issue.

Can anyone help please.

Ps

This is a conventional auto box not the CVT


Andy